Allelopathic effect of Schinus molle essential oils on wheat germination

Gas chromatography-flame ionisation detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS) analyses of the essential oils of leaves and fruits of the ornamental Shinus molle L. were reported and their allelopathic effect on wheat (Triticum aestivum L.) was evaluated. Qualitative and quantitative differences between fruit and leaf oils were observed. Both oils were rich in monoterpene hydrocarbons and the major constituents were limonene and beta-phellendrene (35.9-65.4%), alpha-phellendrene (24.3-20.1%), myrcene (12.8-7.7%) and alpha-pinene (5.9-1.7%) for fruits and leaves, respectively. Both essential oils showed a dose-dependent allelopathic activity on wheat germination and radicle elongation with leaf oil being the more phytotoxic.